The invention relates to tobacco feeding or supplying apparatus in general, and more particularly to improvements in apparatus which can be utilized with advantage for delivery of tobacco to the distributors (also called hoppers) of rod making machines, such as cigarette, cigarillo or cigar rod making machines. Still more particularly, the invention relates to improvements in apparatus which can segregate particles of tobacco (particularly shredded tobacco ribs and/or shredded tobacco leaf laminae) from a gaseous carrier medium preparatory to dumping or another mode of delivering separated tobacco particles into the magazine of the distributor in a rod making machine.
It is already known to install the magazine of a distributor in a cigarette rod making machine beneath a container which is connected to the discharge end of a pneumatic conveyor and has an opening for admission of tobacco particles into the magazine. The particles of tobacco are delivered by a stream of gaseous carrier medium (such as air), and the container has an outlet for evacuation of the gaseous carrier medium. The outlet contains a filter, a screen or a sieve which intercepts the particles of tobacco. The arrangement is such that, when a sensor detects that the upper surface of the tobacco supply in the magazine has descended to a predetermined level, a signal from the detector initiates the flow of a stream of gaseous carrier medium which entrains tobacco particles from a main source of supply. As a rule, the stream of gaseous carrier medium is drawn into the container by suction in a second pneumatic conveyor which receives gaseous carrier medium from the outlet of the container. A detector monitors the quantity of intercepted tobacco particles in the container and transmits a signal when such quantity reaches a preselected value; the signal is used to expose the opening of the container in order to permit the transfer of accumulated tobacco particles from the container into the magazine of the distributor. The opening is thereupon closed and the container is ready to accumulate a fresh batch of tobacco particles.
It is also known to design the apparatus for delivery of tobacco particles to the magazine of a distributor in such a way that the magazine receives an uninterrupted flow of tobacco particles, i.e., that the supply of particles in the magazine is replenished at the rate at which a conveyor draws tobacco from the magazine to form a stream which is thereupon converted into a rod-like filler ready to be wrapped into a web of cigarette paper or other suitable wrapping material.